Deciding which tissue to remove and which to retain is the essential challenge of wound débridement. This is best learned in the operating room from senior surgeons and by supervised practice. Typical errors are failure to remove enough compromised tissue, or to do so in a way that causes additional injury to retained healthy tissue.
Take an organized approach that proceeds in orderly steps through each tissue layer. First, enlarge the traumatic wound for adequate exposure of the whole injury zone. Only minimal non-viable wound margins need to be excised. Explore the depths of the injury zone, and examine it thoroughly. Protect and preserve major blood vessels and nerves, tendon sheaths, healthy periosteum and soft tissue attached to bone.